The present invention relates to a cutter supporting unit adapted in a tire grooving apparatus.
Hitherto, a tire grooving apparatus has, for example, a construction as disclosed in Japanese Unexamined Patent Publication No. 177232/1986 wherein a cutter supporting arm is provided on a supporting stage capable of moving laterally in parallel with a tire supporting shaft for supporting a tire and of moving upwardly or downwardly, and a cutter supporting unit is attached to a rotatable supporting rod which is attached to the cutter supporting arm. This cutter supporting unit is integratedly constituted by a cutter supporting frame fixed to the rotatable supporting rod and a cutter holder, and a cutter is held by the cutter holder with a clamp piece nipping together the cutter and the cutter holder.
Since the conventional cutter supporting unit as mentioned above is integratedly assembled with the cutter supporting arm and the cutter supporting unit itself has an integrated construction, the replacement of the cutter is carried out by removing and fastening the clamp piece located at the end of the tire supporting unit when the replacement of the cutter is required due to wear or breakage or required due to the necessity of changing the groove shape.
However, in the above conventional cutter supporting unit, the replacement of the cutter is not easy because the cutter is heated up in the grooving operation, and much labor and skill are required in an adjustment work at the time of attaching the cutter, for example, an adjustment of the cutter projection length and an adjustment of the bending angle of the cutter by bending into a particular shape, thus it takes a long time to replace the cutter. Therefore, the above conventional cutter supporting unit has a drawback that productivity is lowered particularly when a plurality of tire grooves having different shapes are formed on one tire using cutters having different shapes.
An object of the present invention is to provide a cutter supporting unit which allows a cutter to be replaced even in heated-up condition and which allows an adjustment of the projection length and an adjustment of the bending angle to be carried out separately before attaching the cutter to a tire grooving apparatus toward enhancing tire grooving productivity.